Adjusted figure size

doc/openstack.md

@@ -14,7 +14,8 @@ Moreover, a management network is required over which the MartServer connects to
 2. Attach the MartServer VM to the network
 
 A figure depicting the general setup is shown below:
-![Martoverview](./Martoverview.jpg "Martoverview")
+
+<img src="./Martoverview.jpg" width="500">
 
 ## Extension adjustments
 When performing the proposed approach in a cloud, some connectors have to be configured to gain access to specific information, e.g.,  user credentials.